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	<script type="text/javascript">

		var n1 = 10;
		var n2 = 20;

		var n = n1++; //n1 = 11  n1++ = 10

		console.log('n=' + n);  // 10
		console.log('n1=' + n1); //11

		n = ++n1 //n1 = 12  ++n1 =12
		console.log('n=' + n); //12
		console.log('n1=' + n1); //12

		n = n2--;// n2=19 n2--=20
		console.log('n=' + n); //20
		console.log('n2=' + n2); //19

		n = --n2; //n2=18 --n2 = 18
		console.log('n=' + n); //18
		console.log('n2=' + n2); //18


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